SUPPORTING ELEMENT AND MEASURING DEVICE PROVIDED WITH SUCH A SUPPORTING ELEMENT

Abstract: The present invention provides a supporting element for supporting one or more sensing elements for measuring or sensing of an object, for example a shaft, comprising a fixed part, securable in a fixed position with respect to the object, and two arms, which together with the fixed part are formed from one piece, the arms being mutually connected and which are slightly spring moveable with respect to the fixed part.

Description: SUPPORTING ELEMENT AND MEASURING DEVICE PROVIDED WITH SUCH A SUPPORTING ELEMENT In taking measurements of objects such as shafts 5 and the like, the measurements have to be taken with a high degree of accuracy, as they are often in the order of a few micrometers. Highly reliable measurements need to be able to be taken by repeated use of the same instrument for a set of different objects, as well as by different instruments for 10 different objects. In practice, a point or an end of a measuring probe, a so called linear measuring sensor, is brought into contact with the subject. Such a sensor can, for example, with the aid of displacement of a coil core bar accurately 15 measure such an object. However, the measuring probes of these sensors are very fragile. For example from the European patent application EP-A-0 181 460 it is known to place the end of a measuring element arm, which is spaced away from the body of the 20 measuring element, against the object to be measured instead of the tip of the measuring element itself. However due to the length of the arm and any curvature therein, inaccuraces can occur in the measured results. Hence, the measured results have to be corrected to take into consideration the 25 difference in distance between the end of the arm, with respects to hinge point of the arm, and the distance of the sensor with respects to the hinge point. The present invention aims to further improve, and avoid the disadvantages of, the known measuring devices. 30 The present invention provideε a supporting element for supporting one or more sensing elements for the « measuring or sensing of an object, for example a shaft, comprising a fixed part, secureable in a fixed position with j respects to the object, and two arms, which together with 35 the fixed part are formed from one piece, the arms being mutually connected and which are slightly spring moveable with respect to the fixed part. Furthermore the present invention provides a measuring device for the measuring or sensing of an object, for example a shaft, comprising a supporting element according to the above and a measuring element, wherein a first part is secured to one of the arms and another part of the measuring element is secured to the supporting part so that the first and second parts are moveable with respect to each other. Because the two arms are mutually connected, preferably by means of a connecting piece which is produced along with the arms out of one piece, the mutual displacement of the measuring element parts agrees precisely with that of the arms. Use of a measuring device according to the present invention avoids bringing into contact any part of a fragile measuring element with the subject to be sensed and/or avoids the fact that inaccuraces due to distortion of the supporting element material affects the accuracy of the measured results. The supporting elements and the measuring device according to the present invention are able to be produced for a relatively low cost. Further characteristics, advantages and details of the present invention will become clear with respects to the following description and the accompanying diagram, wherein a partially broken away perspective view of a preferred embodiment of the invention is shown. A supporting part 1 comprises a fixed part 2 which is secured to a frame 3. A shaft A or any other object from which the measurement d has to be taken, is also harnessed to the frame 3. The supporting element 1 further comprises two arms 3, 4 resp. , which are made out of one piece along with the fixed part 2 and which are spring moveable with respects to the fixed part 2. The two arms 3, 4 are connected to each other via a connecting piece 5, wherein a pin 6 is held in position with the aid of a screw thread. In arm 4, near the connecting piece 5, a first part 8 of a schematically shown measuring element 7 is secured, from which a second part 9 is secured in the fixed part 2. In the present embodiment the first part 8 of the measuring element comprises a core or magnetic bar 10 which is moveable in an axial direction in a, not shown in the diagram, coil which is part of the second part 9 of the measuring element. On sensing or measuring the shaft A, the pin 6 is brought into contact with the shaft A, so that adjustment of the pin 6 gives a first indication of the measurement d. The measurement d is accurately ascertained by the position of the magnetic bar 10 with respects to the part 9 of the measuring element, whose position is exactly stationary with respects to the fixed part 2 of the supporting element and thus also the object A. The position of the magnetic bar accurately agrees with the position of the measuring pin 6, due to the fact that the connecting piece 5 passes through the two parallel arms 3 and 4. Part 8 of the measuring element 7 is preferably secured near to the connecting piece 5 in the arm 4, in order to increase the correlation between the pin 6 its position and the magnetic bar 10. The arms 3, 4 are preferably symmetrically aligned with respects to the median plane of the fixed part 2. Furthermore the arms 3, 4 are preferably provided with openings 11 and 12 near the connection with the fixed part 2 and the connecting part 5, so that the movement of the arms 3, 4 with respects to the fixed part 2 is large enough. Not shown is a preferably harmonica like rubber or synthetic sleeve which is associated with the measuring element 9 between the arm 4 and the fixed part 2 in order to prevent the entry of dust etc. The reguested rights are not determined by the hereabove described embodiment, but are rather determined by the following claims.

Claims: CLAIMS 1. A supporting element for one or more sensing elements for the measuring or sensing of an object for example a shaft, comprising: - a fixed part, securable in a fixed position with respects to the object, and - two arms, which together with the fixed part are formed from one piece, the arms being mutually connected and which are slightly spring moveable with respect to the fixed part. 2. A supporting element according to claim 1, wherein the arms are mounted on both sides of the fixed part. 3. A supporting element according to claim 2, wherein the form of the arms is mirror symmetric with respect to the median plane of the fixed part. 4. A supporting element according to claims 1, 2 or 3 wherein an arm is provided with one or more openings. 5. A device for measuring or sensing an object for example a shaft, comprising: - a supporting element according to one of the claims 1 to 4, - a measuring element of which a first part is secured to one of the arms and another part is secured to the fixed part, so that the first and second part are moveable with respects to each other. 6. A measuring device according to claim 5, wherein an adjustable pin is secured in a connecting part, which is formed by the connection between the arms. 7. A measuring device according to claims 5 or 6, characterized in that the measuring element is secured next to the pin in one of the two arms. 8. A measuring device according to claims 5, 6 or 7, wherein the arms are mounted on both sides of the supporting part and which, in front view, form a parallelogram or a rectangle.

Inventors: PRONK HENDRIKUS, PRONK, HENDRIKUS
Applicants: PRONK BEHEER B V H, PRONK HENDRIKUS, H. PRONK BEHEER B.V., PRONK, HENDRIKUS
Application year: 1994
Main classification: B23Q1
IPC codes: B23Q1, G01B7